Campanario, F., Rauch, M., & Sapeta, S. (2014). W+W- production at high transverse momenta beyond NLO. Nucl. Phys. B, 879, 65–79.
Abstract: Pair production of W gauge bosons is an important process at the LHC entering many experimental analyses, both as background in new-physics searches or Higgs measurements and as signal in precision studies and tests of the Standard Model. Therefore, accurate predictions for this class of processes are of great interest in order to exploit the full potential of LHC measurements. We use the LoopSim method to combine NLO QCD results for WW and WW + jet, as well as the loop-squared gluon-fusion contribution, to obtain approximate NNLO predictions for WW production. The cross sections are calculated with VBFNLO and include leptonic decays of the W bosons as well as finite-width and off-shell effects. We find that the size of the additional corrections beyond NLO can be significant and well outside of the NLO error bands given by renormalization and factorization scale variation. Applying a jet veto, we observe further negative corrections at NNLO. which we relate to the presence of large Sudakov logarithms.
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Campanario, F., & Kubocz, M. (2014). Higgs boson CP-properties of the gluonic contributions in Higgs plus three jet production via gluon fusion at the LHC. J. High Energy Phys., 10(10), 173–16pp.
Abstract: in high energy hadronic collisions, a general CP-violating Higgs boson Phi with accompanying jets can be efficiently produced via gluon fusion, which is mediated by heavy quark loops. In this article, we study the dominant sub-channel gg -> ggg Phi of the gluon fusion production process with triple real emission corrections at order alpha(5)(s). We go beyond the heavy top-quark approximation and include the full mass dependence of the top- and bottom-quark contributions. Furthermore, in a specific model we demonstrate the features of our program and show the impact of bottom-quark loop contributions in combination with large values of tan beta on differential distributions sensitive to CP-rneasurements of the Higgs boson.
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Campanario, F., Kerner, M., Ninh, L. D., & Zeppenfeld, D. (2014). Next-to-leading order QCD corrections to W+W+ and W-W- production in association with two jets. Phys. Rev. D, 89(5), 054009–11pp.
Abstract: We present a study of W+W+ jj and W-W-jj production including leptonic decays in hadron-hadron collisions. The full electroweak and QCD induced contributions and their interferences are calculated at leading order. We find that, for inclusive cuts, the interference effects can be large if the jets are produced with large transverse momentum where, however, the production rate is suppressed. We also discuss the vector-boson-fusion cuts and show the validity of the vector-boson-fusion approximation. The next-to-leading order QCD corrections to the QCD-induced channels are also calculated. Compared to the previous calculation, we allow the intermediate W bosons to be off shell. For on-shell W production, we obtain an excellent agreement with previous results. Our code will be publicly available as part of the parton level Monte Carlo program VBFLNO.
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Campanario, F., Kerner, M., Ninh, L. D., & Zeppenfeld, D. (2014). Next-to-leading order QCD corrections to Wgamma production in association with two jets. Eur. Phys. J. C, 74(5), 2882–9pp.
Abstract: The QCD-induced production channels in association with two jets are computed at next-to-leading order QCD accuracy. The W bosons decay leptonically and full off-shell and finite width effects as well as spin correlations are taken into account. These processes are important backgrounds to beyond Standard Model physics searches and also relevant to test the nature of the quartic gauge couplings of the Standard Model. The next-to-leading order corrections reduce the scale uncertainty significantly and show a non-trivial phase space dependence. Our code will be publicly available as part of the parton level Monte Carlo program VBFNLO.
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Campanario, F., Kerner, M., Ninh, L. D., & Zeppenfeld, D. (2014). Z gamma production in association with two jets at next-to-leading order QCD. Eur. Phys. J. C, 74(9), 3085–7pp.
Abstract: Next-to-leading order QCD corrections to the QCD-induced pp -> l(+)l(-)gamma j j + X and pp -> <(nu)lover bar>(l)nu(l)gamma(jj) + X processes are presented. The latter is used to find an optimal cut to reduce the contribution of radiative photon emission off the charged leptons in the first channel. As expected, the scale uncertainties are significantly reduced at NLO and the QCD corrections are phase-space dependent and important for precise measurements at the LHC.
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